Rowland A S, Baird D D, Shore D L, Weinberg C R, Savitz D A, Wilcox A J
Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, NC.
Am J Epidemiol. 1995 Mar 15;141(6):531-8. doi: 10.1093/oxfordjournals.aje.a117468.
The relation between anesthetic gas exposure and spontaneous abortion remains unresolved. We examined the effect of nitrous oxide on spontaneous abortion among female dental assistants. Questionnaires were sent to 7,000 dental assistants aged 18-39 years who were registered in California in 1987; 4,856 (69%) responded. Analysis was based on 1,465 respondents whose most recent pregnancy was conceived while working full time. Women were asked how many hours a week they worked with nitrous oxide during this pregnancy and whether the excess gas was scavenged (vented). Relative risk of spontaneous abortion (through week 20) was calculated using a person-week model. This allowed women with current pregnancies (13%) or induced abortions (10%) to be included for appropriate time periods of risk. A total of 101 pregnancies (7%) ended as spontaneous abortions. An elevation in risk of spontaneous abortion was seen among women who worked with nitrous oxide for 3 or more hours per week in offices not using scavenging equipment (relative risk = 2.6, 95% confidence interval 1.3-5.0, adjusted for age, smoking, and number of amalgams prepared per week), but not among those using nitrous oxide in offices with scavenging equipment. This relation changed little when analyses were restricted to confirmed pregnancies or examined for several types of potential bias. Scavenging equipment appears to be important in protecting the reproductive health of women working with nitrous oxide.
麻醉气体暴露与自然流产之间的关系仍未明确。我们研究了氧化亚氮对女性牙科助理自然流产的影响。向1987年在加利福尼亚州登记的7000名年龄在18 - 39岁的牙科助理发放了问卷；4856人（69%）进行了回复。分析基于1465名最近一次怀孕时为全职工作的回复者。询问这些女性在此次怀孕期间每周使用氧化亚氮工作多少小时，以及多余的气体是否被清除（排放）。使用人时模型计算自然流产（至第20周）的相对风险。这使得当前怀孕的女性（13%）或人工流产的女性（10%）能够在适当的风险时间段内被纳入分析。共有101次怀孕（7%）以自然流产告终。在未使用清除设备的办公室中，每周使用氧化亚氮工作3小时或更长时间的女性自然流产风险升高（相对风险 = 2.6，95%置信区间1.3 - 5.0，经年龄、吸烟情况和每周制备汞合金数量调整），但在使用清除设备的办公室中使用氧化亚氮的女性中未观察到这种情况。当分析仅限于确诊怀孕或检查几种潜在偏倚类型时，这种关系变化不大。清除设备对于保护使用氧化亚氮工作的女性的生殖健康似乎很重要。
